Stool is kinda black / loose .edg normal. found sludge on gallbladder. hida scan normal.. have diverticulosis and hiatel hernia. should i be concerned?

Black Stool?: if your stool is black, that could indicate blood. Do you take Iron? See you doctor to evaluate further.

Rule out bleeding: Whenever there is a history of black stools it is good to make sure that blood is not causing this. If you just had an EGD it is unlikely that you have a bleeding ulcer, but if it was done a while ago this could be a new development. Pepto bismol (bismuth subsalicylate) can also cause black stools, as can iron supplements. A simple guaiac test can quickly rule out a bleed in your gut, so call your Dr! :)